Cooling turbine rotors



e 1949. J. SCHUSTER, JR

COOLING TURBINE ROTORS 2 Sheets-Sheet 1 Filed Aug. 23, 1944 INVENTORV JOHN SCHUSTER, JR.

#0 mm 02 mm Om ATTORNEY 9' J. SCHUSTER, JR

CQOLING TURBINE RQTORS 2 Sheets-Sheet 2 Filgd Aug. 23, 1944 T m .N 0; V v 4 m NQ/NQ Om on on 0: 0: VO 0: Vm OO- h vm 00 J a a ATTORNEY Patented Feb. 8, 1949 UNITED STATES PATENT OFFICE oooLIN'G 'runnma no'roas John Schuster; Jr., Narberth, Pat, assignor to United Aircraft Corporation, East Hartford, Conn, a corporation of Delaware Application mm 23, 1944, Serial No. 550,898

Claims. 1

This invention relates to cooling a turbine rotor particularly in a turbine adapted for operation by hot gases.

The copending application of Bodger, Serial Number 550,871, filed August 23, 1944, describes a rotor having a central bolt through which coolant is circulated to cooling chambers at both ends of the rotor. A feature of this invention is an arrangement of a partition in the cooling chamher to direct the flow of coolant through the chamber.

When the turbine rotor is built up of diskcarrying blades and end elements all held together'by a central bolt the space within the end sections and outside of the'bolt may form a cooling space through which coolant may be circulated for limiting the heat transfer from the power section of the rotor to the bearings on the end elements. A feature of this invention is an arrangement of the cooling chamber to provide a flow of coolant first over the surface of the bolt and then over the inner surface of the end element to assure thorough cooling.

The inner end of the cooling chamber may be closed by packing material and a feature of the invention is an arrangement of a partition in the coolant chamber which also holds the packing in place. Another feature is the formation of this partition as an integral part of the threaded sleeve by which the end element is connected to the central bolt.

. ments. On one of the sleeves (sleeve 60 as shown) the inner thread has a greater pitch than the outer thread so that as the sleevelis screwed into place a tension is applied'to the bolt.

Other objects and advantages will be apparent from the specification and claims, and from the accompanying drawings which illustrate an embodiment oi "the invention.

Figure 1 is a sectional view through the turbine.

Figure 2 is a fragmentary sectional view on a larger scale through the central bolt and end sections of the rotor showing the cooling chambers in detail.

The turbine includes a casing it built up of rings l2, It, It and I8 and supported by radial pins 20 in a housing 22. These pins are slidable within the housing and engage bores in bosses 24 in one ring it of the casing. Rotor 26 within the casing has a number. of rows of blades 2' alternating with the rows of nozzles 30 on the casing rings.

Housing 22 has a head-34 supporting a bearing sleeve 36 for the front end of rotor 28. At the other end of the turbine, housing 22 supports-a mounting 38 within which is a bearing to for the rear end of the rotor. Mounting 38 has a number of'legs l2 engaging with radial pins 44 which support the mounting within the housing.

To assist in aligning the disks'during assembly and to prevent relative rotation in operation each disk has projecting annular flanges 64 and "on opposite sides. these flanges having interengaging elements preferably in the form of face splines cooperating with similar elements on the adjoining disk. The inner ends of shaft elements 54 and 58 have face splines engaging the splines on the end disks.

Gas enters the first stage nozzles of the turbine through an inlet scroll Ill attached to the end of casing l0. Gas is discharged from the turbine through a duct 12 connected to the end casing ring and surrounding the rear bearing mounting.

The shaft elements" 54. and 56 are larger in diameter. than the fastening bolt to form coolant chambers" and I6 surrounding the bolt. Coolant is admitted to the rearward end of the central bolt through a tube 18 mounted in one of the projecting legs 42 of the bearing mounting and connected with a passage 00 in bearing All. A cap I2 on the bearing mounting has a connecting passage 84 by which coolant from passage is guided through a tube 86 extending through a cap. on the end of the bolt.

The bolt has radial passages 90 adjacent its rearward end which communicate with chamber It permitting coolant to flow into this chamber and discharge through one or more grooves 92 in the end element It. At the front end of the bolt, passages 84 permit coolant to flow from the bolt into chamber ll, coolant from this chamber discharging through passages 96 in the end element and adjacent passages 90 in a sleeve loll surrounding said element. A cap I02 at the end of the bolt prevents the flow of coolant from the end of the bolt.

The inner end of chamber I4 is defined by a packing ring "it surrounding the bolt and held in place by a sleeve I08 which may engage the end of sleeve 80. The packing is held against a rib I00 on the. central bolt. Openings H0 near the inner end of sleeve I00 direct coolantfrom the in- 3 side to the outside of the sleeve and the sleeve forms a partition which causes a flow of fluid along the surface of the bolt to the inner end of chamber 14 and then along the inner surface of shaft element 54 to dischar e through passages SI.

Similarly, at the rear end of the turbine rotor, chamber 16 is divided into inner and outer compartments by a sleeve H2 which may, if desired, be integral with sleeve 62 and which engages at its inner end a packing ring I it to hold this ring in place against a projecting rib 6 on element SI. Openings 8 adjacent the inner end of sleeve 2 direct the flow of coolant through chamber 16 so that coolant first flows inwardly along the surface of the bolt and then outwardly along the inner surface of element 56. In this way circulation of coolant through the entire length of chamber I. is assured and thorough cooling of the end element I6 is assured.

It is to be understood that the invention is not limited to the specific embodiment herein illustrated and described, but may be used in other ways without departure from its spirit as defined by the following claims.

I claim:

1. A turbine rotor having an annular chamber through which coolant is circulated, the inlet and discharge for said chamber both being adjacent one end and a substantially cylindrical partition in the chamber having an opening spaced from the inlet and discharge for the chamber and adjacent the opposite end thereof to guide the flow of coolant within the chamber.

2. A turbine rotor including a central bolt, an

end element surrounding said bolt at one end and spaced from the bolt to form a coolant chamber surrounding the bolt, inlet and discharge passages to said chamber adjacent one end thereof, and means for guiding the flow of coolant within the chamber said guide means being constructed to cause axial flow within the chamber.

3. A turbine rotor including a central bolt, an end element surrounding said bolt at one end and spaced from the bolt to form a coo ant chamber surrounding the bolt, inlet and discharge passages to said chamber adjacent one end thereof, and a substantially cylindrical partition within the chamber for guiding the flow of coolant said partition having a passage for fluid adjacent the opposite end of the chamber.

4. A turbine rotor including a central bolt, an end element surrounding said bolt and spaced from the bolt to form a coolant chamber surrounding the bolt, inlet and discharge passages to said chamber, packing at the inner end or the chamber between the element and the bolt, and a cylindrical partition extending through the chamber and engaging the packing for holding the packing in position and for guiding the flow of coolant within the chamber.

5. A turbine rotor including a central bolt, an end element surrounding said bolt and spaced from the bolt to form a coolant chamber around the bolt, inlet and discharge passages to said chamber, packing at the inner end of the chamber between the element and the bolt, and a cylindrical partition extending through the chamber end element surrounding said bolt and spaced from the bolt to form a coolant chamber around the bolt, inlet and discharge passages adjacent one end of the chamber, a cylindrical partition extending through the chamber and enga ing the packing for guiding the flow of coolant, and an opening in the partition at a point axially spaced from the inlet and discharge passages for circulating the coolant in a predetermined path.

7. A turbine rotor including a central bolt, an end element surrounding the bolt adjacent one end and spaced from the bolt-to form a coolant chamber around the bolt, a sleeve connecting the bolt and the end element and forming an end wall of the chamber, and a partition projecting from the sleeve into said chamber for guiding the flow of coolant through the chamber.

8. A turbine rotor including a central bolt, an end element surrounding the bolt adjacent one end and spaced from the bolt to form a coolant chamber around the bolt, a sleeve connecting the bolt and the end element and forming an end wall of the chamber, a partition projecting from the sleeve into said chamber for guiding the flow of coolant through the chamber, and packing at the inner end of the chamber between the element and the bolt to form the other end wall 01' the chamber, said partition engaging and holding the packing in place.

9. A turbine rotor having a number of discs each with a row of blades thereon, a central bolt extending through said discs and holding them in assembled relation, an end element engaging with an end disc, and said element surrounding said bolt adjacent one end and being spaced from the bolt to form a coolant chamber, said end element being held in position by said bolt, a sleeve connecting the bolt and the end element and forming an end wall of the chamber, inlet and discharge passages to said chamber adjacent one end, and a partition projecting from the sleeve into said chamber for guiding the flow of coolant through the chamber, said partition having an opening therethrough at the end remote from said passages.

10. A turbine rotor having a number of discs each with a row of blades thereon, a central bolt extending through said discs and holding them in assembled relation, an end element engaging with an end disc, and said element surrounding said bolt adjacent one end and being spaced from the bolt to form a coolant chamber, said end element being held in position by said bolt, inlet and discharge passages to said chamber, and a cylindrical partition in said chamber for guiding the flow of coolant through the chamber.

. JOHN SCHUSTER, JR.

REFERENCES orrnn The following references are of record in the file of this patent:

UNITED STATES PATENTS 

